Faraz Kalantari
Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, Texas, USA
[ 1 ] - Image-based versus atlas-based patient-specific S-value assessment for Samarium-153 EDTMP cancer palliative care: A short study
Introduction: Use of SPECT/CT data is the most accurate method for patient-specific internal dosimetry when isotopes emit single gamma rays. The manual or semi-automatic segmentation of organs is a major obstacle that slows down and limits the patient-specific dosimetry. Using digital phantoms that mimic patient’s anatomy can bypass the segmentation step and facilitate the dosi...
[ 2 ] - Characterization of low, medium and high energy collimators for common isotopes in nuclear medicine: A Monte Carlo study
Introduction:In an ideal parallel-hole collimator, thickness of septal material should be sufficient to stop more than 95% of incident photons. However, some photons pass the septa without interaction or experience scattering before they reach the detector. In this study, we determined different contribution of collimator responses consist of geometrical response, septal penetr...
[ 3 ] - A model based, anatomy dependent method for ultra-fast creation of primary SPECT projections
Introduction: Monte Carlo (MC) is the most common method for simulating virtual SPECT projections. It is useful for optimizing procedures, evaluating correction algorithms and more recently image reconstruction as a forward projector in iterative algorithms; however, the main drawback of MC is its long run time. We introduced a model based method considering the eff...
[ 4 ] - Assessment of the impact of applying attenuation correction on the accuracy of activity recovery in Tc99m-ECD brain SPECT of healthy subject using Statistical Parametric Mapping (SPM)
Introduction: Photon attenuation in tissues is the primary physical degrading factor limiting both visual qualitative interpretation and quantitative analysis capabilities of reconstructed Single Photon Emission Computed Tomography (SPECT) images. The aim of present study was to investigate the effect of attenuation correction on the detection of activation foci following statistical analysis w...
[ 5 ] - Reducing the respiratory motion artifacts in PET cardiology: A simulation study
Introduction: There are several technical features that make PET an ideal device for the noninvasive evaluation of cardiac physiology. Organ motion due to respiration is a major challenge in diagnostic imaging, especially in cardiac PET imaging. These motions reduce image quality by spreading the radiotracer activity over an increased volume, distorting apparent les...
[ 6 ] - Energy window setting for optimum Tl-201 cardiac imaging [Persian]
Introduction: Poor sensitivity and poor signal to noise ratio because of low injected thallium dose and presence of scattered photons are the main problems in using thallium in scintigraphic imaging of the heart. Scattered photons are the main cause of degrading the contrast and resolution in SPECT imaging that result in error in quantification. Thallium decay is ve...
[ 7 ] - Derivation and validation of a sensitivity formula for knife-edge slit gamma camera: A theoretical and Monte Carlo simulation study
Introduction: Gamma cameras are proposed for online range verification and treatment monitoring in proton therapy. An Analytical formula was derived and validated for sensitivity of a slit collimator based on the photon fluence concept. Methods: Fluence formulation was generalized for photons distribution function and solved for high-energy point sources. The...